title: Synthesis of allylic trifluoromethyl ketones and their activity as inhibitors of the sex pheromone of the leopard moth, Zeuzera pyrina L. (Lepidoptera: Cossidae).
abstract: BACKGROUND
  Trifluoromethyl ketones (TFMKs), structurally related to the pheromones, are good inhibitors of pheromone communication in insects. To determine their activity on Zeuzera pyrina L. (Lepidoptera: Cossidae), a polyphagous pest, the authors have prepared two diunsaturated TFMK analogues of the major (3) and the minor (4) pheromone components, and two monounsaturated ones (5, 6). Their biological activity in electroantennogram (EAG), wind tunnel and field tests is presented.
  
  
  RESULTS
  The synthetic strategy to obtain the allylic TFMKs 3 and 5 is based on the reactions of diene 10 and 1-octadecene with trifluoroacetaldehyde ethyl hemiacetal, followed by Dess-Martin oxidation of the resulting homoallylic trifluoromethyl alcohols. In EAG, topical application of analogues 3 and 4 on male antennae significantly reduced the pheromone response. In the wind tunnel, compound 4 reduced the number of contacts with the pheromone source. In the field, traps baited with mixtures of pheromone and inhibitors captured significantly fewer males than the pheromone alone.
  
  
  CONCLUSIONS
  An efficient synthesis of allylic TFMKs is reported, with good overall yield, regiospecificity and diastereoselectivity. These compounds are good inhibitors of the pheromone in electrophysiology, wind tunnel and field tests. The results show the importance of two unsaturations at positions 2 and 13 of the trifluoroacyl group in the structure of the analogues, the latter being critical for inhibitory activity.
authors.affiliation: Departament de Quimica Biològica i Modelització Molecular (IQAC-CSIC), Barcelona, Spain.
authors.forename: Lourdes
authors.initials: L
authors.lastname: Muñoz
authors.forename: M Pilar
authors.initials: MP
authors.lastname: Bosch
authors.forename: Lluís
authors.initials: L
authors.lastname: Batllori
authors.forename: Glòria
authors.initials: G
authors.lastname: Rosell
authors.forename: Dolors
authors.initials: D
authors.lastname: Bosch
authors.forename: Angel
authors.initials: A
authors.lastname: Guerrero
authors.forename: Jesús
authors.initials: J
authors.lastname: Avilla
mesh_terms: D000475:Alkenes / Q000737:chemistry; D000498:Allyl Compounds / Q000138:chemical synthesis / Q000494:pharmacology*; D000818:Animals; D057506:Arthropod Antennae / Q000187:drug effects*; D005071:Evoked Potentials; D005260:Female; D005426:Flight, Animal / Q000187:drug effects; D066298:In Vitro Techniques; D007659:Ketones / Q000138:chemical synthesis / Q000494:pharmacology*; D058116:Lewis Acids / Q000737:chemistry; D008297:Male; D009036:Moths / Q000187:drug effects*; D012724:Sex Attractants / Q000037:antagonists & inhibitors*; D012726:Sexual Behavior, Animal / Q000187:drug effects*; D014270:Trifluoroethanol / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: D000475:Alkenes; D000498:Allyl Compounds; D007659:Ketones; D058116:Lewis Acids; D012724:Sex Attractants; D014270:Trifluoroethanol